Apparatus and method for testing mechanical endurance of surface of optical disc, the optical disc of same kind as the tested optical disc

ABSTRACT

An apparatus and method for testing mechanical endurance of a surface of an optical disc is disclosed, which includes a rotating plate on which the optical disc is fixed to generate scratch thereon, and rotating the fixed optical disc; and a plurality of abrasion wheels disposed in perpendicular to the rotating plate, and being in contact with the surface of the optical disc, to generate the scratch on the surface of the optical disc, wherein, the scratches generate when the optical disc rotates a predetermined turn, e.g. below ten turns for applying a predetermined load generated from the abrasion wheel on the optical disc.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Korean Application No.10-2003-064034, filed on Sep. 16, 2003, which is hereby incorporated byreference as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and method for testingquality of an optical disc, and more particularly, to an apparatus andmethod for testing mechanical endurance of a surface of an optical disc,the optical disc of same kind as the test disc.

2. Discussion of the Related Art

Up to now, there are recording media such as a magnetic recording tape,a laser disc (LD) or a compact disc (CD) as an optical disc, and adigital video disc (DVD) newly born with a vast recording capacity.

Since the optical disc among the recording media utilizes a digitalrecording system different from the conventional recording system, thatis, magnetic recording system, and has a very small volume and weight,it is efficient and convenient to keep and carry, so that it is a recenttrend for a consumer to prefer the optical disc.

However, even any appliance should be used without any defect, and ifthere were any problem in quality, the consumer's reliability for themanufacturer would be decreased.

This causes more serious problem in the optical disc having minutesignal characteristics and brings inferior quality originated fromscratch, deformity, fingerprint, and attachment of foreign materialduring manufacturing of the product.

Thus, a produced optical disc undergoes the quality test as a nextprocess, and the optical disc is shipped to an optical disc market.

A conventional quality test for an optical disc is generally performedby four measuring drives.

First, on the assumption that the characteristics of optical discsmanufactured by the same equipment are identical, the manufacturer makesa choice of an arbitrary optical disc from all of the manufacturedoptical discs, and loads the selected optical disc onto a measuringsystem.

In the first measuring drive, a high frequency wave signal and a jitterare measured by means of a signal reproduced from the optical disc.

In the second measuring drive, a servo signal (a focusing error signaland a tracking error signal) are measured based on a signal reproducedfrom the optical disc.

In the third measuring drive, the mechanical characteristics of theoptical disc, which undergoes the quality test, are measured.

Finally, in the fourth measuring drive, the optical characteristics ofthe optical disc are measured.

As described above, according to the conventional quality test of theoptical disc, an accuracy of information recording, and the mechanicalcharacteristics and the optical characteristics of the optical disc areinspected.

From these, since a mechanical damage that would occur on an incidentsurface of an information recording/reproducing laser beam during theuse of a high density optical disc, that is, a scratch and the likecauses the deterioration of a signal of an optical disc as well as dataloss, and in more worse case, brings the recording and/or reproducing ofinformation onto the optical disc impossible, the damage takes the mostimportant portion of the quality test of the optical disc.

Accordingly, in order to prevent this problem, a protective coating maybe formed to enhance the mechanical stiffness or hardness of the surfaceof the optical disc.

However, after forming the protective coating on the surface of theoptical disc for this purpose, the mechanical characteristics of theprotective coating should be quantized. Namely, there is need toquantize for how long the protective coating endure the scratch whichwould occur during the use of the optical disc.

There are a pencil hardness test and a taber abrasion test as a test forthe quantization of surface-proof of the high-density optical disc.

The pencil hardness test is an estimating method for estimating thescratch at a hardness value correspondent to a hardness of the pencil atan instant when the scratch occurs by contacting pencils havingdifferent hardness to the optical disc in a rectilinear motion.

However, since the pencil hardness test is a test for generating thescratch by which a human contacts the pencil on the surface of theoptical disc, the pencil hardness test has disadvantages in that it isdifficult not only to maintain the same load continuously, but also togenerate the quantization scratch because the scratch does not occur asmany as desired.

The taber abrasion test is a test to estimate the degree of endurance byuniformly wearing the surface of the optical disc while giving apredetermined load by means of D1004 method of a standard, AmericanSociety for Testing and Materials (ASTM) as a kind of an abrasion wheel.

In the conventional taber abrasion testing apparatus, if an optical discto be scratched is loaded and rotated, a plurality of abrasion wheelshaving a predetermined weight contact the optical disc at aperpendicular position to the optical disc so that scratch the surfaceof the optical disc by a uniform load for at least ten or more rotationsof the optical disc.

At that time, the ASTM defines the load generated from the abrasionwheel less than 9.8N(1000 gf), and there are several kinds such asCS-10F, CS-10, and CS-17 to be used.

The taber abrasion testing apparatus having the aforementioned structureis an equipment designed for the purpose of not testing the mechanicalendurance of the surface of the optical disc by scratching the opticaldisc, but testing the degree of the scratch of general plastic goods.

Therefore, the scratch occurring by the taber abrasion testing apparatusis remarkably different from the scratch generated when the optical discis used actually in a real life.

Namely, the taber abrasion testing apparatus determines the endurance ofthe surface of the optical disc by wearing the surface. This isremarkably different from the situation that real-generated scratch isreacted in a drive (for example, an optical disc drive) for driving theoptical disc by responding the operation.

Therefore, since the manufacturer determines the quality of the opticaldisc by his relative determination with his veteran know-how notquantitative classification according to an actual reference standardwhen to determine the quality of the optical disc poor or good by thetaber abrasion testing apparatus, there are a plenty of errors.Moreover, since the scratches generated on the optical disc in the reallife and by the taber abrasion testing apparatus are different from eachother in the shape, a try to determine the optical disc poor or goodwith only the know-how without an absolute reference value makes vasterrors.

As described above, since, up to now, there is not a special method forquantizing generation degree of the scratch in order to test themechanical endurance of the surface of the optical disc, a quantizationof the degree of the scratch is urgently demanded.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to an apparatus andmethod for testing mechanical endurance of a surface of an optical discthat substantially obviates one or more problems due to limitations anddisadvantages of the related art.

An object of the present invention is to provide an apparatus and methodfor testing mechanical endurance of a surface of an optical disc, toenhance the mechanical characteristics of the surface of the opticaldisc by quantizing the characteristics of the mechanical endurance.

Another object of the present invention is to provide an apparatus andmethod for testing mechanical endurance of a surface of an optical disc,to improve reliability and decrease a testing cost.

Another object of the present invention is to provide an apparatus andmethod for testing mechanical endurance of a surface of an optical disc,to test and determine the quality of an optical disc as a good or poorone with rapidness and accuracy by setting a realizable absolutereference value.

Another object of the present invention is to provide an apparatus andmethod for testing mechanical endurance of a surface of an optical disc,to improve reliability in testing the mechanical endurance of thesurface of the optical disc by generating a scratch having a similartype to that of a scratch generated in a real life.

Another object of the present invention is to provide an apparatus andmethod for testing mechanical endurance of a surface of an optical disc,to improve reliability in testing the mechanical endurance of thesurface of the optical disc such as BD-RE (Blu-ray Disc-REwritable) andBD-WO (Blu-ray Disc-Write Once) which records information aftergenerating a scratch on the surface of the optical disc.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, anapparatus for a scratch endurance of a surface of an optical discincludes a rotating plate, on which an optical disc is loaded androtating the optical disc, and a plurality of abrasion wheels being incontact with the surface of the optical disc, to generate a scratch onthe surface of the optical disc, the being generated during the opticaldisc rotates a predetermined turns while the abrasion wheels apply apredetermined load on the optical disc, wherein the apparatus determineswhether the optical disc has a predetermined endurance by comparing ajitter value from the scratch generated on the surface of the opticaldisc with a predetermined jitter value.

Herein, the optical disc is formed of any one of BD-RE (Blu-rayDisc-REwritable), BD-WO (Blu-ray Disc-Write Once), and BD-RO (Blu-rayDisc-Read Only).

Also, the load of the abrasion wheel, applied on the optical disc, is ina range between 0.49N(50 gf) and 7.35N(750 gf).

Also, the scratch generated on the surface of the optical disc has adepth between 0 μm and 2 μm, and the abrasion wheel is any one ofCS-10F, CS-10, and CS-17.

Herein, the scratch generates when the optical disc rotates apredetermined turn, e.g. below ten turns, during applying the load of0.49N(50 gf) to 2.45N(250 gf) on the surface of the optical disc withthe abrasion wheel of CS-10F. Or, the scratch generates when the opticaldisc rotates below ten turns during applying the load of 1.47N(150 gf)to 4.41N(450 gf) on the surface of the optical disc with the abrasionwheel of CS-10. Or, the scratch generates when the optical disc rotatesbelow ten turns during applying the load of 2.45N(250 gf) to 7.35N(750gf) on the surface of the optical disc with the abrasion wheel of CS-17.

In another aspect of the present invention, a method for testing ascratch endurance of a surface of an optical disc includes the steps ofcontacting a plurality of abrasion wheels with a predetermined load tothe surface of the optical disc, maintaining the contact between theoptical disc and the abrasion wheels until the optical disc rotates apredetermined turns, and determining whether the optical disc has apredetermined endurance by measuring a jitter value obtained from asignal of reproducing information recorded on the optical disc.

In another aspect of the present invention, a method of testing ascratch endurance of a surface of an optical disc includes the steps ofcontacting a plurality of abrasion wheels with a predetermined load tothe surface of the optical disc to generate a scratch on the surface ofthe optical disc, comparing a jitter value obtained from a signal ofreproducing information recorded on the optical disc with apredetermined jitter value, and determining whether the optical disc hasa predetermined endurance based on a result of the comparing step.

In another aspect of the present invention, an optical disc, the opticaldisc is made by the same manufacturing process as the tested opticaldisc

In another aspect of the present invention, an information recordingmedium having an entrance surface, which has a sufficient resistance ornot with respect to a scratch, the information recording medium can beverified or is the same kind of the disc verified by a test to determinewhether the surface of the information recording medium has a sufficientresistance, wherein the test includes the steps of contacting aplurality of abrasion wheels with a predetermined load to the surface ofthe information recording medium to generate a scratch on the surface ofthe information recording medium, comparing a jitter value obtained froma signal of reproducing information recorded on the informationrecording medium with a predetermined jitter value, and determiningwhether the information recording medium has a predetermined endurancebased on a result of the comparison.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiments of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 illustrates a schematic view showing a taber abrasion testingapparatus according to the present invention;

FIG. 2 illustrates a flowchart showing a method of testing mechanicalendurance of a surface of an optical disc for BD-WO (Blu-ray Disc-WriteOnce) according to the present invention;

FIG. 3 illustrates a flowchart showing a method of testing mechanicalendurance of a surface of an optical disc for BD-RE (Blu-rayDisc-REwritable) according to the present invention;

FIG. 4 illustrates a flowchart showing a method of testing mechanicalendurance of a surface of an optical disc for BD-RO (Blu-ray Disc ReadOnly) according to the present invention;

FIG. 5 illustrates a view explaining a predetermined scratch patterngenerated on an optical disc by using a micro-scratch tester accordingto the present invention;

FIG. 6 illustrates a graph showing a scratch depth depending on a loadof an abrasion wheel applied on an optical disc according to the presentinvention; and

FIG. 7 illustrates a graph showing a change of jitter values dependingon a load of an abrasion wheel applied on optical disc according to thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

FIG. 1 illustrates a schematic view showing a taber abrasion testingapparatus according to the present invention.

As described in FIG. 1, an apparatus for testing mechanical endurance ofa surface of an optical disc includes a rotating plate 20, and aplurality of abrasion wheels 10. On the rotating plate 20, an opticaldisc 30 to be scratched is loaded, for rotation of the loaded opticaldisc 30. Also, the plurality of abrasion wheels 10 are disposed inperpendicular to the rotating plate 20, for the contact with the opticaldisc 30, and generation of scratches on the surface of the optical disc30.

The abrasion wheels contacted with the optical disc are also rotated toa direction according to the rotation of the optical disc, one wheelbeing rotated to reverse direction with respect to the other abrasionwheel.

In this state, the scratches generate when the optical disc 30 rotates apredetermined turn, e.g. below ten turns for applying a predeterminedload generated from the abrasion wheel 10 on the optical disc 30.

The optical disc 30 may be BD-RE (Blu-ray Disc-REwritable), BD-WO(Blu-ray Disc-Write Once), or BD-RO (Blu-ray Disc-Read Only).

That is, the optical disc 30 may be used of any one of an optical discon which no information is recorded, an optical disc on whichinformation is recorded one time, and an optical disc on whichinformation is recorded more than one time.

Also, it is preferable to maintain the load generated from the abrasionwheel 10, applied on the optical disc 30, between 0.49N(50 gf) and7.35N(750 gf).

In this case, the scratch generated on the surface of the optical disc30 may have a depth between 0 μm and 2 μm.

Also, the abrasion wheel 10 may be used of any one of CS-10F, CS-10, andCS-17.

Under the condition of using the abrasion wheel of CS-10F in the presentinvention, the load between 0.49N(50 gf) and 2.45N(250 gf) is applied onthe optical disc, and the optical disc rotates below ten turns, so thatthe scratch generates on the surface of the optical disc.

Under the condition of using the abrasion wheel of CS-10 in the presentinvention, the load between 1.47N(150 gf) and 4.41N(450 gf) is appliedon the optical disc, and the optical disc rotates below ten turns, sothat the scratch generates on the surface of the optical disc.

Under the condition of using the abrasion wheel of CS-17 in the presentinvention, the load between 2.45N(250 gf) and 7.35N(750 gf) is appliedon the optical disc, and the optical disc rotates below ten turns, sothat the scratch generates on the surface of the optical disc.

A method for testing mechanical endurance of the surface of the opticaldisc according to the present invention will be described as follows.

FIG. 2 illustrates a flowchart showing a method of testing mechanicalendurance of a surface of an optical disc for BD-WO (Blu-ray Disc-WriteOnce) according to the present invention.

Referring to FIG. 2, first, the optical disc is fixed on the rotatingplate, and then the rotating plate rotates together with the opticaldisc (S10).

Subsequently, the abrasion wheel contacts on the surface of the opticaldisc being rotated (S20), and the contact load between the optical discand the abrasion wheel is increased to a preset level (S30).

At this time, it is preferable to maintain the load generated from theabrasion wheel, applied on the surface of the optical disc, between0.49N(50 gf) and 7.35N(750 gf).

Under the condition of using the abrasion wheel of CS-10F, the loadbetween 0.49N(50 gf) and 2.45N(250 gf) is applied on the surface of theoptical disc. In case of using the abrasion wheel of CS-10, the loadbetween 1.47(150 gf) and 4.41N(450 gf) is applied on the surface of theoptical disc. In case of using the abrasion wheel of CS-17, the loadbetween 2.45(250 gf) and 7.35(750 gf) is applied on the surface of theoptical disc.

Next, the contact load between the optical disc and the abrasion wheelis maintained continuously until the optical disc rotates below tenturns, whereby the scratches generate on the surface of the opticaldisc. Then, the abrasion wheel is spaced apart from the surface of theoptical disc (S40).

After that, the testing apparatus records information on the opticaldisc having the scratches (S50), and determines whether the quality ofthe optical disc is good or poor by measuring a jitter value from asignal of reproducing the information recorded on the optical disc(S60).

FIG. 3 illustrates a flowchart showing a method of testing mechanicalendurance of a surface of an optical disc for BD-RE (Blu-rayDisc-REwritable) according to the present invention.

As shown in FIG. 3, first, the optical disc is fixed on the rotatingplate, and then the rotating plate 20 rotates together with the opticaldisc (S100).

Subsequently, the abrasion wheel contacts on the surface of the opticaldisc being rotated (S101), and the contact load between the optical discand the abrasion wheel is increased to a preset level (S102).

At this time, it is preferable to maintain the load generated from theabrasion wheel, applied on the surface of the optical disc, between0.49N(50 gf) and 7.35N(750 gf).

Next, the contact load between the optical disc and the abrasion wheelis maintained continuously until the optical disc rotates below tenturns, whereby the scratches generate on the surface of the opticaldisc. Then, the abrasion wheel 10 is spaced apart from the surface ofthe optical disc (S103).

Subsequently, the testing apparatus records information on the opticaldisc having the scratches (S104), and determines whether the informationrecord number of the optical disc is correspondent to the presetinformation record number (S105).

At this time, the preset information record number may be in a rangebetween 1 and 1000.

If it is determined that the information record number of the opticaldisc is correspondent to the preset information record number, thetesting apparatus determines whether the quality of the optical disc isgood or poor by measuring a jitter value from a signal of reproducingthe information recorded on the optical disc (S106).

However, if it is determined that the information record number of theoptical disc is not correspondent to the preset information recordnumber, the testing apparatus performs again the process step ofrotating the optical disc by the rotating plate.

FIG. 4 illustrates a flowchart showing a method of testing mechanicalendurance of a surface of an optical disc for BD-RO (Blu-ray Disc ReadOnly) according to the present invention.

As shown in FIG. 4, first, information is recorded on the optical discby the testing apparatus (S201).

Subsequently, the testing apparatus fixes the optical disc, on which theinformation is recorded, to the rotating plate, and then rotates theoptical disc by the rotating plate (S202).

After that, the abrasion wheel contacts on the surface of the opticaldisc being rotated (S203), and the contact load between the optical discand the abrasion wheel is increased to a preset level (S204).

Herein, it is preferable to maintain the load generated from theabrasion wheel 10, applied on the optical disc 30, between 0.49N(50 gf)and 7.35N(750 gf).

Next, the contact load between the optical disc and the abrasion wheelis maintained continuously until the optical disc rotates below tenturns, whereby the scratches generate on the surface of the opticaldisc. Then, the abrasion wheel is spaced apart from the surface of theoptical disc (S205).

Then, the testing apparatus determines whether the quality of theoptical disc is good or poor by measuring a jitter value from a signalof reproducing the information recorded on the optical disc (S206).

FIG. 5 illustrates a view explaining a predetermined scratch patterngenerated on an optical disc by using a micro-scratch tester accordingto the present invention.

Referring to FIG. 5, the testing apparatus according to the presentinvention maintains the contact load between the optical disc and theabrasion wheel until the optical disc rotates below ten turns, togenerate the scratch on the surface of the optical disc.

FIG. 6 illustrates a graph showing a scratch depth depending on a loadof an abrasion wheel applied on an optical disc according to the presentinvention.

FIG. 6 is a graph of comparing a bare disc having no coating layerthereon with a hard-coated disc having a coating layer thereon.

As shown in FIG. 6, when generating the scratch having a depth of 2 μmor more, servo errors of the bare disc having no coating layer and thehard-coated disc having the coating layer are observed.

That is, when performing the test for endurance of the surface of theoptical disc, the scratch having the depth of 2 μm is defined as anabsolute reference value for determining whether the quality of opticaldisc is good or poor. By testing the mechanical endurance of the surfaceof the optical disc, it is possible to quantize the generation degree ofthe scratch.

FIG. 7 illustrates a graph showing a change of jitter values dependingon a load of an abrasion wheel applied on optical disc according to thepresent invention.

In FIG. 7, when the bare disc having no coating layer and thehard-coated disc having the coating layer are used, each of the baredisc and the hard-coated disc rotates by one turn and five turns, andthe abrasion wheel of CS-10F is used.

As shown in FIG. 7, since the servo error having the jitter value above10% or more generates, when the load is measured at a range between 50gf and 750 gf, the load is preferable at a range between 250 gf and 500gf below the jitter value of 10%.

Accordingly, in case of using the hard-coated disc, the load generatedfrom the abrasion wheel is quantized to 50 gf to 750 gf, and isdifferently set according to the kind of abrasion wheels.

That is, in the taber abrasion test, under the condition of using theabrasion wheel of CS-10F, the optical disc rotates below ten turns, andthe load is controlled at a range of approx. 50 gf to 250 gf.

In case of using the abrasion wheel of CS-10, the optical disc rotatesbelow ten turns, and the load is controlled at a range of approx. 150 gfto 450 gf.

Also, under the condition of using the abrasion wheel of CS-17, theoptical disc rotates below ten turns, and the load is controlled at arange of approx. 250 gf to 750 gf.

Therefore, in all cases from the soft abrasion wheel of CS-10F to thehard abrasion wheel of CS-17, the load of the surface of the opticaldisc is quantized between 50 gf and 750 gf.

Accordingly, the rotation number of the optical disc is decreased belowten turns, thereby reducing the abrasion degree of the optical disc bythe abrasion wheel at minimum. As a result, it is possible to generatethe scratch having a type that is very similar to that of the scratchgenerated in a real life, thereby enhancing the reliability in testingthe mechanical endurance of the surface of the optical disc.

In other words, the scratch on the optical disc in the real life isgenerated by being scratched few times, on the contrary, the more timesthe abrasion wheels are scratched, the more the scratch during severalrotation of the optical disc by using the taber abrasion tester makes adifference from the scratch in real life due to abrasion of ambientoptical disc to be scratched.

In this reason, there is a problem in the reliability for the mechanicalendurance test of the surface of the optical disc due to the scratch,and then this is the worst serious problem occurring in the mechanicalendurance test of the surface of the optical disc according to theconventional art.

According to the present invention, since the number of turns of theoptical disc can be reduced to one turn at minimum to ten turns atmaximum value by the quantized-absolute reference value, the reliabilityof the mechanical endurance test of the surface of the optical disc canbe enhanced by causing the scratch of type the closest the scratch inthe real life.

Also, it is possible to test the endurance of the surface of the opticaldisc by generating the scratch on the surface of the optical discthrough one turn of the optical disc at minimum. As a result, it isdetermined whether the quality of optical disc is good or poor witheasiness and precision.

Furthermore, the mechanical characteristics of the surface of theoptical disc may be quantized to the BD-RE available for the repetitiverecord reproduction, and the BD-WO available for one recordreproduction.

Meanwhile, the apparatus and method for testing the mechanical enduranceof the surface of the optical disc according to the present inventionextracts a predetermined number of optical discs among the manufacturedoptical discs, and performs the test for the mechanical endurance withthe extracted discs. If the discs have the endurance according to thepresent invention, it is assumed that other discs, not extracted for thetest, also have the mechanical endurance, that is, the scratchendurance.

As mentioned above, the apparatus and method for testing the mechanicalendurance of the surface of the optical disc according to the presentinvention have the following advantages.

First, the generation degree of the scratch is quantized to enhance themechanical characteristics of the surface so that the preservation ofdata according to achievement for the high-density of the optical disccan be increased.

Second, since the quality of the optical disc is tested easily andprecisely, the reliability of the optical disc can be enhanced.

Third, the scratch can be formed as much as to wish in a short time sothat the testing time for the mechanical endurance test of the surfaceof the optical disc can be also decreased and the manufacturing cost maybe reduced.

Fourth, the method for testing the mechanical endurance according to thepresent invention may be applied to the BD-RE available for therepetitive record reproduction, and the BD-WO available for one recordreproduction, with satisfaction.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. An apparatus for testing whether an optical disc is acceptable,comprising: a rotating plate configured to support an optical disc; anda plurality of abrasion wheels configured to contact a surface of theoptical disc and to generate a scratch on the surface of the opticaldisc, the abrasion wheels being configured to rotate in a rotatingdirection of the rotating plate or in an opposite rotating direction ofthe rotating plate, the scratch being generated while the optical discrotates five turns, and while the abrasion wheels apply a load on theoptical disc, wherein the apparatus is configured to record informationon the scratched optical disc, and to determine whether the optical discis acceptable by comparing a jitter value from the information recordedon the scratched optical disc with a predetermined reference jittervalue.
 2. The apparatus according to claim 1, wherein the load of theabrasion wheels, applied on the optical disc, is in a range between0.49N(50gf) and 7.35N(750gf).
 3. The apparatus according to claim 1,wherein the abrasion wheels are configured to generate the scratch suchthat the scratch generated on the surface of the optical disc has adepth between 0 μm and 2 μm.
 4. The apparatus according to claim 1,wherein a type of the abrasion wheels is any one of CS-10F, CS-10, andCS-17.
 5. The apparatus according to claim 1, wherein the abrasionwheels are configured to generate the scratch if the optical discrotates while the abrasion wheels apply the load on the surface of theoptical disc, the load being 0.49N(50gf) to 2.45N(250gf), the abrasionwheels being of type Cs-10F.
 6. The apparatus according to claim 1,wherein the abrasion wheels are configured to generate the scratch ifthe optical disc rotates while applying the load on the surface of theoptical disc, the load being 1.47N(150gf) to 4.41N(450gf), the abrasionwheels being of type CS-10.
 7. The apparatus according to claim 1,wherein the abrasion wheels are configured to generate the scratch ifthe optical disc rotates while applying the load on the surface of theoptical disc, the load being 2.45N(250gf) to 7.35N(750gf), the abrasionwheels being of type CS-17.
 8. The apparatus according to claim 1,wherein the type of the abrasion wheels is Cs-10F.
 9. A method fortesting whether an optical disc is acceptable, comprising: applying aplurality of abrasion wheels to the surface of the optical disc, theoptical disc being supported by a rotating plate, the abrasion wheelsrotating in a rotating direction of the rotating plate or in an oppositerotating direction of the rotating plate, and the abrasion wheels beingapplied with a load; maintaining the contact between the optical discand the abrasion wheels until the optical disc rotates five turns;recording information on the optical disc having a scratch, the scratchbeing generated while the optical disc rotates and while the abrasionwheels apply a load on the optical disc; and determining whether theoptical disc is acceptable by comparing a jitter value obtained from asignal of reproducing the information with a predetermined referencelitter value.
 10. The method according to claim 9, wherein the load ofthe abrasion wheels, applied on the optical disc, is in a range between0.49N(50gf) and 7.35N(750gf).
 11. The method according to claim 9,wherein a type of the abrasion wheels is any one of CS-10F, CS-10, andCS-17.
 12. The method according to claim 9, wherein the applying stepapplies the abrasion wheels such that the scratch is generated if theoptical disc rotates and applies the abrasion wheels with the load onthe surface of the optical disc, the abrasion wheels being of typeCS-10F, the load being 0.49N(50gf) to 2.45N(250gf).
 13. The methodaccording to claim 9, wherein the applying step applies the abrasionwheels such that the scratch is generated if the optical disc rotateswhile applying the load on the surface of the optical disc, the abrasionwheels being of type CS-10, the load being 1.47N(150gf) to 4.41N(450gf).14. The method according to claim 9, wherein the applying step appliesthe abrasion wheels such that the scratch is generated if the opticaldisc rotates while applying the load on the surface of the optical disc,the abrasion wheels being of type CS-17, the load being 2.45(250gf) to7.35(750gf).
 15. The method according to claim 9, wherein thedetermining step determines that the optical disc is acceptable if thejitter value is not greater than a reference jitter value.
 16. Themethod according to claim 9, wherein the type of the abrasion wheels isCS-10F.